Circuit breaker



Nov. 16, 1948. F. e. VON HOORN CIRCUIT BREAKER 2 Sheets-Shoat 1.

Original Filed June 25, 1943 LVN-Er w Inventor:

von

Fred G. Hoorn, 103 Z M- Abbor'ne g H is F. 53. VON HOORN cmcun BREAKER Nov. 16, 1948..

2 sheets-sheet 2 ori inal Filed June 25, 1943 Inventor: Fred G. Von Hoor-n, by 51f; (5W

His Attorney Patented Nov. 16, 1948 unrrao s'rAras 2,454,196 cmcm'r BREAKER t Fred G. you H to General New York 492,284, Paten 1 1,1941, Serial No.

Claims.

The present application constitutes a division di g application Serial No. 492,284 now Patent No. 2,422,508, issued June 11, 1947, and entitled Circuit breaker, and which is assigned to the same assignee as the present application.

My invention relates to circuit breakers, more particularly to manually operated current responsive circuit break object a simple and reliablecircuit breaker provided with circuit breaker closed by the event or an overload, calibrating the d a se holding the together my invention in one form I pivoted arm on the supporting framebreaker which cooperates d with the normally secured the circuit breaker in such predeter- K the curelectric shunt for the current is secured to the a circuit breaker pro- Fig. 2 is a fragmentary the line 2-2 of Fig. 1 looking in Fig. 3 is a fragmentary view or a part or the ure 4 is a side elevation partially in section of the is held by oorn, Bridgepo Electric Company,

circuit breaker shown in Fig. 1, but with the mechanism in the manually position; and Fig. 5 is a similar elevation partially in section or the circuit breaker, but with the mechanism in the overload tripped position.

In carrying out my invention in one form I provide a spring contact am Hi mounted on a pivot ll between two upright sides of a supporting framework i2, only one side oi which is shown, The arm comprises a oted on the pivot H and provided with a stop projection 13 and an This member has secured to its rivets ii, the spring arm ill on is secured a movable contact 11 cooperating with a stationary contact 18.

As shown in Fig. 1, the breaker closed circuit position by means of is held in its a toggle convigil!! application lune. 25,

101. zoo-11c) intermediate point of a breaker byv moving a handle Connq assignor a corporation 0 1943, Seria No dated June is application April sisting of two links I! and 20, the lower end of the link ,20 being pivotally connected by a pivot 2| to the operating projection ll, end of the link I! is connected by pivot 22 normally fixed trip arm leis broken to open th in rth'e drawing, the handle being an inverted U-shaped operating member, only one arm 25 of which is seen, which embraces the supporting 'framework i2 and has of its arms pivoted on lateral projections 28 secured to the framework. A pair of helical tension springs 21, only which is shown. are provided on opposite the toggle. Each spring has one end 28 of the toggle and its other upper end connected to the handle 25. Thus when the handle is'moved left until the center left of the pivot 22. the pivot 28- toward the left thereby opening the circuit breaker. In its open position the projection i3 rests against a stop pin 29. The manually opened position of the mechanism is illustrated in Fig. 4.

Normally the left-hand end 30 oi the arm 23 is secured by engagement with the end of a screw 3! carried by a thermostat 32, whereby 23 is held against movement in a clockwise direction about its pivot 32a by the force applied by the occurrence of a prede- 32 moves toward ,the left far enough to release the arm 23 which thereupon arm to an open circuit the mechanism is illusthe other.

position 7 25 carrying the handle, while its In order that the arm 23 may be held in the shown in Fig. l of the drawing, even though it has been released by the thermostat, l. have provided .a lever 33 forming a connecting member mounted on the fixed pivot 32a. The lower end of this lever engages the operating arm end engages an Actually which are porting framework, (not shown) on the opposite side of the tramwork mounted also on the pivot 32a. The upper ends of these arms are connected t ther by a the arm effects the 35 vertically extending portion 34 on the arm 23. an aperture at each en The lever 33 furthermore is so arranged that tures the conduc ors 38 and 46 extend. Thus to when the arm 23 is in its normal secured posiremove the shunt the nuts 49 and 50 are removed pivot 26 so that the arm is in appreciable spaced nuts 50 and BI tightly down against it so as to relation from the stop 38 It will be observed 23 term a good mechanical, and also good electrical,

that the forces are applied entirely by the helical connection at each end between the shunt and spring 21. but since it is acting almost directly the conductors themselves. The outer nut 43 on on the arm 23, its force applied to the arm 23 the conductor 38 is the usual clamping nut for overpowers the relatively small amount of its effecting an electrical connection with an exteri'orce which opposes movement of the handle tonal circuit. ward the left hand. Therefore, the handle is Also, adjustment of the current response oi the moved slightly away from stop 38. thermostat, or rather of the amount of deflection However, ii it is desired to hold the circuit required 01' the thermostat to release the arm 23, done by moving the handle24 toward the right It is contemplated, however, that this screw will ment with the arm 23 moves the arm slightly in a I 25 effected by applying a suitable shunt 41 a ma b 4 is held firmly in the exact position shown in understood that any current value above the parthat the contact arm will be held against openclosed manually by means of the handle 24, as

ing movement previously described.

The latching end 30 of the arm 23 is prefer- Another feature 01 the circuit breaker is a dustably a metal part which is secured to the end of tight and substantially a and liquid-tight seal e electrically insulated from the arm 23 wt e aperture of e casing through which the e mechan m as shown, is enclosed in hand extends To provide for this seal, the casing or housing 37 made of a molded electrihandle is provided with an arcuate portion 52 ex cally insulating material at the bot or which tending in the direction of its motion this arcue supporting framework I is secured Electriate portion having for its center the pivot of the cal connections are made with the circuit breakhandle on the projection 26. By means of a comas mostat 32 whose lower end is electrically and shown in Fig. 2, the arcuate portion 52 with the w contact "3 is mounted on a conducting strap 43 55 ridges in the upper surface of the casing. Thus secured to he c nd c r 39 y a nu 4 as shown in Fig 2, e handle is provided with a The circuit t rough the circuit breaker beridge 55 and groove 56 on each side of the apertween the external connectors 38 and 39 may be ture through which the handle extend traced from the connector 38 through the thero facilitate this mounting of the handle on rnostat 32 to its upper end and then through a 60 the inverted U-shaped metal operating member extends directly on the exterior f the sin in accordance with the force applied by the from the conductor 38 to the conductor 46. spring 54.

From the conductor 46 a flexible conductor 48 A second stop 59 limits ,the movement of the leads to e end of the Contact and the arm 25 in a counterclockwise direction, and a circuit then leads through the two contacts and stop 60 is provided on the frame, against which the conductor 39 to the exterior of the circuit 7 the end of the contact arm comes to rest in the breaker. open circuit position.

Calibration or change in the tripping current When the arm 23 is moved clockwise on overvalue is effected v'ery conveniently from the exload to open the circuit breaker, it can be brought terior of the casing by interchanging the shunt back with its end 30 in latching engagement with :onductor 41 for one having a suitable electrical the screw 3| by means of the handle, assuming a,4o4,1oo I that the thermostat is allowed to cool and brin when said operating member is held in its closed the screw back into latching position. To eiiect circuit position.

this, the handle may be moved in either direo- 3. A circuit breaker comprising a trip arm tion. mounted on a tilted pivot, current responsive when the trip arm 23 is' released by the thermeans normally holding. said trip arm in a premostat, the spring 21 causes it to move clockwise determined position, a link having a first end about its pivot 32.. At the same time the trip pivotally mounted on said trip arm at an interarm, by engagement with the cross rod 35, moves mediate point 01 said trip arm, a pivoted operatthe lever 33 clockwise so that the lever a in turn ing member, an over-center spring having moves the operating arm 25 counterclockwise l0 ends connected respectively to the other end of about its pivot 26. This movement of the opersaid link and to said operating member whereby ating member 25 carries the upper end 01 the said operating member can be moved to snap spring 21 toward the pivot 21, the pivot and the said iink irom one position to another, circuit spring moving toward each other. when the control means operated by said link, said trip arm pivot reaches a position to the right 0! the'center when released by said current responsive means line of the spring,-the spring snaps the toggle to biased by said spring to move said first end of its broken position thereby opening the circuit said link toward said spring to eflect automatic breaker. During this opening movement. the operation of said circuit control means, and a spring biases the handle toward the leit to a cenlever mounted on a fixed pivot having one end tral position in which aproiection ii on the operarranged for engagement with said operating ating member it rests against a stop projection member and its other end in engagement with 82 (Fig. 3) on the trip arm 23. The trip arm 23 said trip arm whereby said operating member is brought to rest by the engagement oi the cross may be held to prevent movement of said trip rod 35 with the projection 03 on the frame as arm. showninFig. 5. 25 e 4. A circuit breaker comprising a trip arm 11 the handle it after this automatic opening mounted on a med pivot, current responsive is moved toward the left, the engagement oi the means normally holding said trip arm in a preproieotion 8i with the projection 01 on the trip determined position, a link having a first end arm 21 effects counterclockwise movement oi the pivotally mounted on said trip arm .at an interam until its leit-hand end is moved downward mediate point of said trip arm, a pivoted o erat to its latching position. On the other hand, it ing member, an over-center tension spring havthe handle is moved toward theright hand irom ing its ends connected respectively to the other this central position, its engagement with the end of said link and to said operating member lever 33 causes this lever to reset the lever 21 whereby said operating member canbe mov while at the same time the circuit breaker is 35 snap said nk from one position to another, cirosed. me

While I have shown a particular embodiment trip arm when released'by said current respon- 01 my invention, it will be understood, oi course, sive means being biased by said spring to move that I do not wish to be limited thereto since said first end of said link toward said spring to many modifications may be made, and 1 thereeflect automatic operation oi said circuit control iore contemplate by the appended claims to cover means, and a lever mounted on said pivot 01 any such modifications as all within the true trip arm having one end in engagement with said 5a, ranged tor abutting en agement with said nip spirit and scope oi! my invention perating member and its other end arrang or What I clai new an esire to secure y engagement with said trip arm wh by said op- Letters Patent oi the United states is: 5 erating member y eld to prevent move- 1 The combination in a rcui breaker 01 m ment 0! said trip arm and whereby movem t o pivoted trip arm norm held by a current resaid trip arm hen release said current responsive means in a predetermined an ular posisponsive means produces movement of said opertion, means tor moving said trip arm when reating member and said spring toward leased by (1 current responsive means to open end oi link.

the circuit breaker, a pivoted operating member 5. In a circuit breaker provided with a trip movable in the same angular direction to close member normally held by a current responsive the circuit breaker as said trip arm moves to open means in a predetermined angu ar position said circuit breaker, and a lever pivotally an operating member movable between closed unted at an intermediate point of said lever and o en circuit positions to open and close the and having its ends arranged tor abutting encircuit breaker, the combination therewith of a gagement with said trip arm and said operating movabiy mounted connecting member to member respectively for causing simultaneous an operating connection between said operating ember and said trip member when said o erater. 2. The combination in a circuit breaker or a w ing member is in its closed circuit position so ivoted trip arm normally held by current rethat when said operating member is held in its sponsive means in a predeterm ned angu ar p closed circuit position said trip member is see sition, means for moving said trip arm when reagainst movement when released by said current leased by said current res onsive means to open responsive means.

- FRE G. von HOORN.

the circuit breaker as said trip arrnmoves to open REFERENCES CITED sa d ir u e and -1 N mounts The following references are of record in the ed at an intermediate point oi said lever on the m this patent:

pivot trip arm and via: its ends arq},

UNITED STATES PATENT arm and said operatin member respectively for Number Home Date preventing tri ping movement oi said trip arm 2,162,511 Gen June 18, 1939 fo/II/II/ Certificate of Correction Patent No. 2,454,106. November 16, 1948.

FRED G. VON HOORN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 6, line 15, claim 3, after means insert the word being;

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 29th day of March, A. D. 1949.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents.

Certificate of Correction Patent No. 2,454,106. November 16, 1948.

FRED G. VON HOORN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 6, line 15, claim 3, after means insert the Word being;

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of March, A. D. 1949.

[SEAL] THOMAS F. MURPHY,

Assistant Gommissioner of Patents. 

